1. Field of the Invention
The disclosure relates to a backlight assembly and a liquid crystal display device using the same, and more particularly to a backlight assembly and a liquid crystal display device using the same in which bright lines generated from lamps arranged in parallel are prevented, while its volume and thickness are minimized and brightness is maximized.
2. Description of the Related Art
Generally, a liquid crystal display (LCD) device displays images using liquid crystal. Liquid crystal converts light that does not contain information into light containing information to display images. The LCD device includes a liquid crystal (LC) control part for precisely controlling the liquid crystal and a light supply part for supplying light to the LC control part.
In particular, the light supply part greatly influences the display quality of the LCD device. Specifically, the light supply part influences display brightness, power consumption, and thickness and volume of the LCD device.
Recently, the size of an LC control part considerably increases as the display area of an LCD device becomes larger. As a result, the amount of the light that is supplied from the light supply part to the LC control part also increases.
Recently, there has been a development in the structure of an LCD device in which a plurality of light sources, for instance, cold cathode fluorescent lamps, are arranged in parallel below the LC control part in order to supply enough light to the increased area of the LC control part. The structure in which a plurality of light sources are arranged in parallel below the LC control part is called “direct-illuminating type LCD device”.
A conventional direct-illuminating type LCD device has an advantage in that a sufficient amount of light can be supplied to the LC control part. However, the conventional direct-illuminating type LCD device also has disadvantages in that the brightness becomes non-uniform and the thickness and volume of the LCD device increase.
In order to prevent the display quality from being deteriorated due to the non-uniform brightness, the conventional direct-illuminating type LCD device utilizes a light diffusion plate for diffusing the light generated from the light source.
However, even though the light diffusion plate is used, the conventional direct-illuminating type LCD device still has the drawback in that bright lines generated from the lamps are shown from the outside of the light diffusion plate depending upon a pitch and a gap. The pitch is a distance between light sources (lamps), and the gap is a distance between the light sources and the light diffusion plate.
Specifically, if the gap between the light sources and the light diffusion plate increases while the pitch between the light sources is fixed at a constant value in order to eliminate the bright lines, the brightness decreases abruptly, so that the display quality is seriously lowered. In this case, the thickness and the volume of the direct-illuminating type LCD device increase.
On the contrary, if the gap decreases while the pitch is fixed at a constant value, the problem due to brightness is solved, but bright lines are shown and are perceived by a user, so that display failure occurs.
Also, if the pitch increases while the gap is fixed at a constant value, the brightness that influences display quality is largely lowered, so that the display quality is lowered.
On the contrary, if the pitch decreases while the gap is fixed at a constant value, the brightness is largely enhanced, but the number of the bright lines increases and power consumption increases.